


Supernova

by buttcat



Category: Sherlock (TV)
Genre: Anal Sex, Body Swap, First Time, M/M, Masturbation, Science Fiction, Total Idiocy
Language: English
Status: Completed
Published: 2013-07-26
Updated: 2013-07-28
Packaged: 2017-12-21 09:16:23
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 6
Words: 9,178
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/898558
Author URL: https://archiveofourown.org/users/buttcat/pseuds/buttcat
Summary: <blockquote class="userstuff">
              <p>John wakes up in Sherlock's body. He's a little too enthusiastic about it.</p>
            </blockquote>





	1. Chapter 1

Of all the idiotic, scatter-brained things John had done in his lifetime, he had the feeling he'd forever regret this one in particular. He walked with his shoulders hunched, his elbows pulled in tight to his body, trying to ward off the hundreds of eyes he could feel burning into his back - mothers with their babies, fathers herding groups of toddlers about, camp group counselors and their young protegees - every single one of them dissecting him, evaluating him, criticizing his every movement as he trailed behind his companions. He could hardly bear it. 

Why in God's name did he think it was a good idea to bring Sherlock to a children's museum? The detective was loving it, of course. He dashed about from room to room, enthusiastically pointing out inconsistencies in the colourful placards that went along with the exhibits, scoffing at the taxidermy ("so sloppy!"), and declaring its explanations of natural disasters "disgustingly incomplete" at the top of his voice. John tried his hardest to hush him but it was impossible. 

It hadn't been his idea, not really. Harry's latest girlfriend had a little daughter of her own, and he really _did_ owe his sister a visit, since he'd been so wrapped up in his work lately and really quite neglectful, and little Becky had just been _begging_ to go to the children's museum for weeks, and John could you please just do this one favor for me, please? 

She'd told him he could bring Sherlock along with him, just for something to do. "Like a double date," Harry had said. John had told her to stuff it.

Then he'd gone home and asked Sherlock how he felt about museums. 

Now he was here, chasing after the incorrigible detective, while Harry, her date, and her small child followed behind him bemusedly, pretending not to know them. He was lucky the museum was tailored to be a "hands-on" experience, because Sherlock was insistent on putting his hands all over everything. He was unafraid to push his way to whatever he wanted, and at the moment he'd just shoved aside two six-year-old girls so he could run his fingers over a replica Egyptian tablet.

"It's fake," he declared, sounding personally wounded. 

"Obviously, Sherlock. It's plaster," John said, trying to ignore the nasty look the girls' mother was giving them.

"But it says on the card, see? 'A sample of ancient Egyptian hieroglyphs.'" 

"Do you really expect a children's museum to put out _actual_ Egyptian artifacts to manhandle?"

"Yes," said Sherlock. "I do. Even if most of its patrons are idiots."

The mother gave out an angered _harumph._ "Sherlock, they're _children,_ " said John wearily. 

"And?" said Sherlock. "Doesn't change the fact that they're incurably stupid."

Harry, who had been hovering nearby for the entire conversation, snickered very loudly. 

John couldn't take much more. He grabbed Sherlock's wrist and tugged him into a side room, away from - people. Harry followed right behind.

It was dark, and empty of other museum patrons - quite perfect, really. There was an enormous plasma ball in the middle of the room, purple-blue tendrils snaking out from its core. It was at least the size of a large beach-ball. 

"Oh, I love these things," Harry said behind him. "John, you ought to try it out."

John rolled his eyes. "Absolutely not." 

He looked over to Sherlock for support, but to his surprise, he seemed oddly enthralled by the device. 

"Fascinating," said Sherlock. "Did you know Nicola Tesla invented these to study high-frequency currents? He wanted to see how they'd behave in an evacuated space."

"What?"

Sherlock briskly stepped over to it. "Come on, John," he called. "I'll demonstrate for you." 

John pinched his eyes shut, took a deep breath through his nose, let it out heavily from his mouth, and stomped over to join Sherlock next to the plasma ball.

"Tesla named it the _inert gas discharge tube,"_ Sherlock was saying. "Hardly an elegant term, but a good sight better than _plasma_ \- oh!"

They'd both put their hands on the ball at the same time. Several things happened at once. 

As soon as their flesh touched the glass surface, every last hungry finger of energy leapt at once to latch on to their palms. For a fraction of a second it appeared as if they were connected by some ethereal ribbon that writhed and twisted at their touch, and in that moment John felt something surge straight through his entire body, his stomach dropping as if he were falling. From the expression he saw on Sherlock's face, it seemed as if he'd experienced about the same.

And then it shattered. 

It exploded outward in all directions. Harry shrieked. Heavy chunks of glass arched to the floor around their feet, glistening like diamonds in the darkness.

John grabbed Sherlock's arms. "Are you all right?" he said, panicked. 

"I'm fine," said Sherlock, and he was. His hands and forearms were untouched, as were his clothes. John inspected his own hands and realized he'd come out unscathed as well.

_"Bloody hell,"_ said someone from the doorway.

Several museum guards had gathered around the mouth of the room. 

"Ah, Christ," John muttered. They didn't look pleased.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~ 

John had meant to go out for dinner with Harry afterwards, but instead he found himself in the kitchen at 221 B Baker, snacking on jam and toast. Sherlock was rummaging about in the refrigerator next to him, completely nonplussed. 

Considering the circumstances, they had been very lucky. The plasma ball had been old, and was about to get replaced anyway, so it wasn't a huge loss. They'd been let off on the stipulation that they never return again. 

Sherlock took this news in stride. John had the impression that he'd been banned from museums before, and this was par for the course.

Halfway through his third piece of toast, he yawned explosively. His limbs felt like limp noodles and his eyelids kept fluttering shut of their own accord.

"Sherlock, I'm going to bed, all right?" he said. "Try not to - look, just don't do anything adventurous, okay?"

Sherlock peered up at him from the fridge, and John was startled to see how exhausted and haggard he looked. "I think I'll join you," he rumbled, and in a delicate moment before he realized what he'd actually meant, John's heart seized in his chest. _He meant he's going to sleep, stupid,_ John chided himself. _Not - anything else._

"All right," John said. "Good, actually. You ought to sleep more."

Sherlock grunted. "I'm not going to make it a habit."

"Of course not," said John. "That'd just be silly, now, wouldn't it? Sleeping every day?"

"Good night, John."

John slept straight through the night. He didn't have a single dream. 

~~~~~~~~~~~~~~~~~~~~ ~~

When John woke, his mouth tasted odd. 

He couldn't put a finger on it. It wasn't sour, like morning breath, and it wasn't the chemical sweetness that collects on your gums when you fall asleep with a sweet in your mouth. It was just different, not good or bad. His teeth felt strange, too, like they were the wrong size. His tongue sat strangely in between them, large and overwhelmingly... _wrong._ Something was wrong. 

He reached to rub his nose on his pajama sleeve and found his face wasn't where it usually was. Nor was his hand. 

He stared at it with groggy eyes. It was spindly and _huge,_ he realized. He didn't pay much attention to his hands normally, but he knew these were not... right. They had neatly trimmed, pearly nails, no grime underneath, and they were the colour of marble.

These weren't his hands, but he'd seen them in action a thousand times before - holding up the arm of a corpse, shuffling through manila folders, stroking over the surface of a replica Egyptian tablet - 

"Sher _lock,"_ he bellowed in a voice that was not his own.


	2. Chapter 2

They stood in the bathroom side-by-side, watching themselves in the cloudy mirror over the sink. John raised his hand to wave at himself - but it was not his body that moved in the mirror, it was Sherlock's, and it was Sherlock's brows that furrowed with worry and Sherlock's eyes that blinked when he willed himself to do so.

"How can you stand being this short?" Sherlock asked. He was contorting John's face into every manner of expression, his fingers - John's fingers - feeling the muscles move under the skin, cataloging each movement. 

"Stop that, would you?" John snapped. "We've got ourselves into - God, I don't even know what this is, Sherlock! This isn't the time!"

Sherlock stroked his hands over his cheeks, feeling the stubble rake over his hands. "My goodness, you need a shave, John."

"Are you even _listening _to me? Do you even _care?_ Sherlock, I want my damn body back!" __

__Sherlock peered thoughtfully at John's calloused, scarred hands. "I'm listening, John. But unless you've got some sort of brilliant plot to switch us back, I think we might as well make the most of a... unique situation."_ _

__John sighed. "You're right. Of course you're right. But - hey! No experiments, okay? Nothing dangerous. I want my body back intact."_ _

__"I won't do anything I wouldn't do to myself."_ _

__That was less than reassuring. "Just don't - oh, forget it. I'm going to take a shower."_ _

__"I just showered yesterday morning."_ _

__"Exactly."_ _

__John reached for his towel and slung it over his shoulder. Sherlock didn't move._ _

__"If you don't mind, Sherlock - ?"_ _

__"Hm? What, you want me to leave? That's absurd. It's _my -_ "_ _

__"Yeah, I realize that. I still don't want to shower in front of you, okay?"_ _

__Sherlock sighed dramatically. "Fine," he said. He tried to sweep out of the room, but the dramatic motion was less than effective when preformed with John's body._ _

__John shut and locked the door behind him, fumbling with the latch. He undressed very clumsily, his arms far too long for the movements he was making. He was still trying to move like John Watson, he realized, and not Sherlock Holmes. He didn't think he'd be able to mimic the graceful, eclectic way Sherlock moved his limbs, so he settled with holding them at a distance from his body, slowing his motions and taking his time._ _

__As he took off the pyjama top, he couldn't help but marvel at how thin Sherlock really was. The bones in his chest showed through - _his sternum,_ his brain spat out reflexively, _his manubrium -_ and his concave stomach was overshadowed by the two points of his hipbones, below which was - _ _

__John swallowed nervously. He tried not to let his eyes travel downward below that bellybutton but they did anyway, down, down, down that pearly stretch of skin, down to the waistband of his trousers. His eyes snapped back up to safer territory, but it was just as strange and oddly arousing to see a soft blush spread across Sherlock's ridiculous cheekbones._ _

__Embarrassed, he averted his eyes and slipped out of his trousers quickly, stepping into the shower. The hot water pounded down on him, massaging his broad back, his taut ass -_ _

__Goddammit._ _

__He absolutely had an erection. It throbbed gently, steadily, utterly distracting and utterly shameful. Somehow, someway, he was trapped in Sherlock's body, and all he could do was think about damn gorgeous the man was._ _

__He recalled Sherlock's words earlier - _might as well make the most of a unique situation._ And, well - really, what harm could it do, if he explored this magnificent body? Sherlock wouldn't ever know. And _goddamn_ was he hard._ _

__He snaked one of those soft, lovely hands up to his chest and brushed his fingers against a nipple._ _

__"Oh, Jesus," he whispered, and gave up. He seized Sherlock's bobbing cock with his other hand and began to pull himself off hard._ _

__It was incredibly hot, and strange, and wonderful. It felt different than when he touched himself, in his own body, but not entirely so; some things were still the same, like the white-hot pleasure that coursed through his veins, and the urgent, tight feeling in his gut, but other things were utterly different - the weight and shape of the cock in his hand, the places that made him shiver when he brushed them with his thumb. He started to fuck his hand, rocking back and forth in the shower, fingers teasing his nipples relentlessly. He had to work very hard not to moan aloud, though a few small whimpers still managed to leak through his lips. Sherlock's lips, and Sherlock's moans._ _

__This is how it feels, he thought in wonder, when Sherlock touches himself. The thought nearly brought him to the edge, flooding his mind with images of his flatmate shaking with pleasure, trousers about his ankles, pumping himself hard and fast. It was an image he'd considered before, but now it was a much more solid idea - he knew what he really looked like, what he really sounded like. _Sherlock._ _ _

__Tentatively, he slipped his hand back behind him. He touched two fingers to the cleft of his ass._ _

__Immediately, a spark of pleasure surged from the spot, and he circled them lower, lower, until he was teasing his entrance softly, brushing those two fingers over himself. His breath was coming fast and hard, now, his mind jumbled beyond thought, beyond realization. The rest of the world faded into the background._ _

__He slipped in a single finger and the feeling was nearly overwhelming. Those long, talented fingers - ! He slid it in and out of himself, searching, feeling, testing the waters -_ _

__"Oh, God," he whispered throatily. He'd found Sherlock's prostate, he was sure of it, and with it his whole body felt as if it was giving off sparks, as if fireworks were going off underneath his fingers. "Fuck," he said, and that was it; the sound of that word in Sherlock's gravelly voice drove him over the edge and he was coming, coming so hard he was shaking, so hard he couldn't think._ _

__When he finished, he collapsed to the floor of the shower, bony knees pulled up to his chin. He felt as if he was made of jelly. It was a good ten minutes until he felt steady enough to move again._ _

__It wasn't until he'd toweled off and put his pyjamas back on that he realized he hadn't ever actually shampooed his hair._ _


	3. Chapter 3

When he wandered into the living room, it was to find himself completely naked, small notepad in hand. It took him a moment to process what he was seeing.

"Bloody - Sherlock, put some damn clothes on! Jesus."

Sherlock looked up at him, a serene expression on his face. It looked so out of place on John's features that it was a little disconcerting.

"I'm cataloging, John. Clothes would defeat the purpose. Besides, all your clothes are hideous anyway."

"My clothes are not - they're _sensible,"_ John said heatedly. "But that's beside the point - what the hell are you cataloging that I'd need to be naked for?"

"Your scars," said Sherlock calmly, and John felt his stomach drop. "They're very interesting. You ought to tell me the stories behind them, though I've mostly deduced them for myself. This one, for instance, is a cigarette burn - fascinating! And self-inflicted, it seems - "

He stopped, his eyes searching John's - _Sherlock's_ \- face.

"Not good?"

John sputtered. " _No._ Not good. Horrible, terrible, _worst -_ "

Sherlock was frowning. "I just wanted to see," he said. "I was curious. And it isn't hurting you."

"It _is,_ though, Sherlock. It's - oh my God, how do I explain this? Scars are very personal, okay? They're not all some sort of, I don't know, heroic badge of honor. Some of them hurt to think about. You can't just _go looking at them without my permission._ "

"They hurt?" Sherlock said. The expression he was making made John's face look extraordinarily confused, and it was almost comical.

"Yes, Sherlock. Jesus, I can't believe this. Do you not - ?"

Sherlock looked at him blankly. John sighed and reached up to run a hand through his hair, but missed horribly and gave up.

"Okay, Sherlock. Fine. That cigarette burn, then - you want to know how I got it?" Sherlock was staring at him, his eyes unnaturally wide. "It wasn't self-inflicted, though I'm not surprised you thought it was. The person who did it tried to make it look as if it was. He sat on my back, and pressed it into my skin, and I was too weak to fight back. I cried, Sherlock. Do you understand why I might want to keep that private?"

Sherlock didn't say anything. He just sat and watched with John's eyes.

"I'm going to - I'll be in my room, okay? And could you, could you _please_ put some _fucking clothes on,"_ John snarled, his voice breaking. He stalked up the stairs and slammed the door behind him.

Guilt began to settle in almost as soon as he'd plopped down on his bed. He shouldn't have been so harsh, really. Sherlock was naturally curious, and a little socially clueless - okay, a lot - so how was he supposed to know John was tetchy about his scars? It bothered him that he'd been so... careless with his body. He hadn't even asked permission.

_Then again,_ his brain whispered, _you went ahead and masturbated with_ his _body. You used him. In contrast, Sherlock is practically blameless._

John curled up in a ball of shame, his stomach churning. He really, really shouldn't have violated Sherlock's privacy like that. It'd been a stupid idea, good God, the stupidest he'd ever had. The trip to the museum paled in comparison. 

Lying on his side, it was near painful to press his knees together just because they were so bony. He was so uncomfortable, so out of place in this body. It was too big, and too lanky, and he didn't know how to move with it. And he missed seeing Sherlock operate this body, missed the graceful way he scrambled through the flat with it. He wanted to be himself again, solid and compact, stubbly in the morning and a bit ruddy. He wanted that temptation gone - the temptation to touch this lovely figure, run his hands all over it, to stand naked in the mirror and stare. 

He sat up and swung his legs over the side of the bed. He really ought to apologize, he realized. He should apologize, and then things would go back to normal, and they could work together to find some way to fix this mess - this idiocy - and they could return to the way things were beforehand, when John was John and Sherlock was Sherlock and neither of them violated the other's privacy in horrible ways. 

He went to stand, but paused midway when he heard something rustling about his bedroom door.

Something dark poked underneath the door - the notebook Sherlock had been using to catalog his scars. It took him a couple tries to shove it through, and it jammed a little bit, but eventually it went all the way through. He could see his own shadow through the crack, and knew Sherlock was waiting to see what he'd do.

He picked it up, and flipped up the cover. 

It was, as advertised, a catalog of scars. His scars. 

_Lft index 2nd joint,_ he read. He knew exactly which scar Sherlock was talking about, a thin one he'd inflicted upon himself when he'd tried to cook an anniversary dinner for a girlfriend. Never again. _.7 cm. Kitchen accident; paring knife._ Yup. _Delicate._ Delicate?

_Rgt knuckle 1st + 2nd + 4th_ was next on the list. That he'd gotten when, in a fit of drunken rage, he'd smashed a mirror. His hand had been pretty torn up, and even now he was a bit embarrassed by these scars. _Various - 7 cm lngth. Forceful blow (window, mirror?). Rough, but beautiful - shaped like flowers._

Beautiful? John had to reread it again to make certain he'd gotten it right. Yes, there it was: _beautiful - shaped like flowers._ How odd. Reflexively, he stroked the fingers of his left hand against the knuckles of his right, though there were no scars on these hands. Sherlock must be a quick healer, John figured, because he'd certainly seen the man get injured. 

He read through the rest of the notebook, his heart in his mouth. Sherlock thought the shrapnel removed from his side left a lovely pattern, an abstract painting in rebuilt tissue. Sherlock thought the ropy trail left across his abdomen by a knife, which he'd acquired during a case not too long ago, was a testament to his steadfast strength, a sweet reminder of their time together. Sherlock thought the bullet wound through his shoulder looked like a dying galaxy. A supernova. 

His head was spinning. He dropped the notebook on the bed and strode over to the door, wrenching it open. He saw himself standing there, sheepishly, a silly grin on his face. 

"I just wanted to say - " Sherlock began, and before he could continue, John grabbed him by the shoulders and pressed him close. 

"I'm sorry," John mumbled, bending down so that his lips were even with Sherlock's - wait, no, _his -_ ear. John felt him smile.

"I should be apologizing," he said. "I just - I didn't realize I should've asked."

"It isn't your fault, Sherlock. I shouldn't have yelled."

"No, you shouldnt've," said Sherlock, and John laughed.

"You're great at this whole apology thing."

"You said it wasn't my fault. Make up your mind." 

John pulled him closer, tightening his grip on Sherlock's back. 

"It's a bit odd, isn't it," Sherlock said. "Being hugged by me, I mean. I'm so _bony._ I don't understand how you stand it." 

John laughed. "All the more reason to fix this, then." 

"Agreed," said Sherlock.

"You got any ideas?"

"I have a theory," said Sherlock. "It's stupid, but it's all we've got."


	4. Chapter 4

John followed Sherlock into the living room, where he started to shrug on his coat. A jolt of panic ignited in John's gut. He really, really would prefer if they stayed out of the public eye. Sherlock was bound to say something rude, and _he'd_ get the blame for it. There was absolutely no way he could let him leave the flat until they sorted this out.

"Where're you off to?" 

"Toy store," said Sherlock. 

"What? Why?"

"To get a portable plasma ball, of course."

"Ah," John said. "Of course. How about I go instead, okay?"

"You're afraid I'll do something stupid with your body."

"Not stupid, just tactless."

Sherlock sighed. "Fine. Whatever. Go ahead, if it makes you happy."

"It does," John said. "Where am I headed?"

"Two blocks down, take a left onto the main road. It's on that strip. They've got rainbow kites hanging in the windows, you can't miss it."

"Right. I'll be back in a bit."

He set out, triumphant. Sherlock, hopefully, would stay indoors for the remainder of their time spent in the other's body, and no major damage would be done. He'd have to keep a close eye on the detective, though, he realized. He'd rather not let him leave his sight. Horrifying images flashed through his mind - Sherlock going downstairs and antagonizing Mrs. Hudson, Sherlock going down to the sandwich shop and pitching a fit, Sherlock meeting up with Mycroft - oh, God. He picked up his pace. 

The toy shop was, as Sherlock had said, impossible to miss. It had a colorful hand-painted storefront and flags of all sorts jutting out above the window. It was all very whimsical. 

The inside was packed with toys. There were a number of cluttered shelves placed haphazardly about, and they all nearly touched the ceiling. It was very dark and a bit stifling. 

The clerk at the desk perked up when he saw him. "Hello there, Mister Holmes!"

"What?" said John, forgetting for a moment the visage he was currently sporting. "Er, yes. Hello."

"What're we looking for today?"

"Er. A - plasma ball? Preferably the largest one you've got, I suppose."

"Okay," the clerk said, looking at him oddly as he walked around the desk. "We've got a couple, I think, over here. Let's see." He disappeared into the maze of shelves for a moment, and came back with a large box in his arms. 

"It's the biggest one of the lot. Thirty centimeters around. Is that okay?" He plopped it on the desk.

"It'll have to do," said John, and pulled his wallet out. "How much?"

"Well, let's see. Asking price is thirty-five quid, but with an employee discount - that's, uhh, about thirty." He winked playfully at John. 

"Right," he said slowly. He passed over the bills, and the man began to wrap it up for him.

"How's John, then?" he asked. "Getting along all right?"

"Ah - ? Fine. He's fine."

"You sure? Usually you've got more to say about him. You lads have a row?"

John filed this tidbit away for later. "I'm just in a hurry," he said, which was entirely true. "Thanks much." He snatched the bag off the counter and scuttled away.

"Come back soon, Mister Holmes," the clerk said to his back. John looked over his shoulder and waved, then scrambled down the street, anxious to return to the flat.

_Come back soon, Mister Holmes._ Did Sherlock go there often? And he'd given him an employee discount when obviously, Sherlock didn't work there, so they must've been... friends? No. Acquaintances. 

He debated over whether or not to ask Sherlock about it all the way back to the flat. When he arrived, his flatmate was lounging on the sofa, a pose that looked comfortable and even elegant on Sherlock, but really looked a bit goofy on John. 

"Did you get it?" Sherlock said, not even bothering to look up.

"Yep," said John. "You owe me thirty quid, by the way."

"Fifteen."

"Fair enough."

It took under two minutes to unpack the device and set it up on the table. It had an awfully short plug, so John had to untangle an extension cord from a snarl of wires nested in a kitchen drawer. Sherlock flipped off the lights and shut the curtains, more for dramatic effect than anything else. 

They stood and stared at it. Comparatively it was very underwhelming.

"You sure about this?"

"No," said Sherlock. He nudged the plastic base with his knuckle and made a face. "This is silly."

"It was _your_ idea."

"You didn't discourage me, did you? Put your hand on it on three."

"Sherlock - "

"One."

"Oh, my God."

"Two."

John readied his hand.

" _Three - "_

They lunged, and grasped it at precisely the same time. The electricity played under their fingers, brilliant in the dark, heavy air of the kitchen, and - 

Nothing happened. 

John realized the very tips of their fingers were overlapping a bit, and he wondered at how rough his hands seemed underneath Sherlock's soft flesh. He had flat, milky nails, he thought distantly. Sherlock's were so pretty compared to his. 

"This is," Sherlock said after a pause, "tremendously idiotic."

John nodded his assent. They both pulled away. John realized his palms were a bit sweaty, and he wiped them off on his trousers.

The plasma ball continued to flicker. John crossed his arms.

"What now?" he asked. 

"We have to... expand our horizons."

"Expand - ?"

Sherlock's phone bleeped, and he pulled it from his pocket. He flicked his eyes over the message, stuck out his lower lip pensively, and tapped out a quick answer.

"Lestrade," he said. "There's been a double homicide. Both victims torn to shreds, no murder weapon in sight."

"Ah," said John. "I'll get my coat, then."

"Yes, do," said Sherlock, pocketing his phone, and John sighed to himself. What on _earth_ were they supposed to tell Lestrade? Maybe he wouldn't notice. John could be proper arrogant at times, if he tried. And all this time around Sherlock had certainly aided his deductive powers: he wasn't as fast as Sherlock, or as accurate, but he could figure out a victim's occupation, marital status, and general demeanor if he had enough time -

Yeah, Lestrade was going to notice.

John reached for his coat out of habit, then chuckled and grabbed Sherlock's. It really was quite a nice coat. Very long, and swishy, and dramatic, and though it wasn't really John Watson's style it suited Sherlock perfectly. He didn't mind wearing it one bit. 

It felt incredibly strange to follow himself down the stairs and out the door. It felt like a dream sequence, almost, following the top of his head down the street ahead of him. He watched himself flag down a taxi, and wondered at how light his eyelashes looked in the sun, nearly invisible. His hair, too - was he really beginning to gray? Ah, dear. 

He clamored into the taxi behind Sherlock, navigating his long, spindly limbs into the back seat. Sherlock watched with interest as he gawkily adjusted his elbows and knees to fit comfortably, bashing them against the cab's interior as he did so. 

"It's quite fascinating to watch you move," Sherlock said. "It's as if you're trying to operate a much smaller body."

"I feel like a teenager," John grumbled.

"Where to?" the taxi driver called back as they started to roll forward.

"Clarke Children's Museum," said Sherlock.

"Wait - sorry, what? The murder's at the museum?"

"Of course not, John. Don't be absurd."

"Then - what - ?"

"We're off to visit their new plasma ball." Sherlock's face dropped a bit. "Did you really think I'd force you to go to the crime scene? Like this?"

"Well, yeah," said John. "I mean..." he paused, unsure of how to go on.

"John, I saw how you reacted earlier, and I - I don't entirely understand, or agree, but I don't want to hurt you. I wouldn't want to force you into... that." Sherlock cleared his throat. "I told Lestrade we were both deathly ill and utterly unable to see anyone. He sends his regards, by the way."

"Oh," said John. "I... see."

A quiet, uncomfortable moment passed. The cabbie had switched the radio off and was now listening intently, his eyes flickering back and forth between the road and his rear-view mirror.

"Thank you," John croaked softly. Sherlock patted his hand.

"I really do try, you know. To be... considerate."

"Not nearly hard enough," John teased. "You nearly sent Molly into conniptions when you pointed out her lipstick - "

"I'm not trying for _Molly,"_ Sherlock scoffed. "What would be the point in that? I'm only trying for you," he added, so softly John would've thought he'd imagined it, if not for the way he'd squeezed his hand afterward. 

John stared at him in disbelief. He'd turned his head away, his eyes fixed firmly out the window - and was that a blush creeping around the side of his cheek? Was Sherlock _blushing?_

They sat in silence for the rest of the ride, though they kept their hands clasped tightly together between them the entire time. _For comfort,_ John told himself. After all, it had been a very tiring day.

_It was for comfort._


	5. Chapter 5

They got out at the museum. Security guards were milling about near the entrance, stopping people before they went in.

"There's no way we're going to get in there, Sherlock," said John.

"Not through the front, no," Sherlock said. "Come on."

John followed. His head was still spinning from their conversation in the cab, and he was simply too confused to argue.

They went around the side of the building. "Fire escape," Sherlock said smartly, pointing. 

"The window's going to be locked, Sherlock."

"Doesn't matter."

Sherlock backed up a few meters, took a running start, and leapt at the bottom rung of the ladder. He missed by several inches and landed awkwardly. 

John snickered. "Here, let me."

"You're so bloody short," Sherlock groused, moving out of the way. 

John got it on his first try. He held it down to allow Sherlock up, giving him a little boost with his other arm, and then followed himself. 

It wasn't a particularly large museum, and they only had to go up three floors to reach the window. Sherlock tried to lift it and gave a disappointed grunt when he found he couldn't.

"Told you," said John. "Now what?"

"Check my left pocket, would you? There should be a knife in there."

John did. There was half a cigarette (damp), a bit of bloody cloth, an unwrapped lemon drop coated in lint, Lestrade's badge, and, finally, a slender knife with a pretty, opalescent handle. He passed it to his flatmate without a word.

"This is an old building, I think," Sherlock explained, leaning in close to the windowsill. "I should probably be able to - ah!" The knife slid effortlessly through the gap between sill and window, and Sherlock grinned. He began to wriggle it around. 

John peered down at the street below. No one seemed to have noticed, but it really was only a matter of time before one of the guards happened to look up. He silently urged Sherlock to hurry. 

"Almost there," Sherlock said, jimmying the knife back and forth. "I've just got to catch the latch. Ah, there it is - "

The window sprung open a few inches with a satisfying pop. Sherlock wormed his fingers underneath and pushed it up the rest of the way. 

"Shall we?" he asked, and wormed his way through, beckoning for John to follow. John had a bit more trouble getting himself through, as he kept misjudging the length of Sherlock's spindly legs, and he tumbled down to the carpeted floor on the other side with a soft thud. Sherlock hushed him.

"Forgive me," he said dryly. Sherlock ignored him.

They were in a long corridor filled with portraits of notable scientists and a sizable collection of large potted ferns. It turned off to the side sharply at either end, so that neither Sherlock nor John could see round the corner. 

"What floor was it on?" John asked. 

"The second. Oh, for Chrissakes, look - they've credited Thomas Morgan with the discovery of sex determination chromosomes. Anyone with half a brain would know it was Nettie Stevens' work that - "

A security guard rounded the corner, and the two dove behind a potted plant. 

"He only got credit because he published first," Sherlock grumbled. John shushed him.

The guard trotted by, hardly an inch from their hiding place. John could hardly believe how absurd it was. Here they were in the middle of the day, crouched behind a decorative fern at a children's museum as if they were undertaking some sort of grand espionage. He could hardly take himself seriously.

"C'mon," he muttered as soon as the guard had turned the corner. He pulled Sherlock up by the forearm and they hurried down the corridor, checking over their shoulders as they went. 

The hall opened up into a larger room, and they glommed onto the back of a tour group of elementary students, trying to look inconspicuous. 

"Over there," Sherlock murmured, pointing past a plaster dinosaur. "Stairs."

They picked their way over carefully, staying behind the exhibits as best they could. When they were within a meter of the door, a woman opened the door to the stairwell, and they ducked underneath her outstretched arm.

"Pardon," John said, swishing past. She looked awfully confused.

The second floor was larger than the first, but Sherlock seemed to know exactly where to go. _He's probably got the whole place mapped out in his head, hasn't he,_ John speculated. He followed his companion faithfully, dodging behind placards and statues whenever possible.

It took some effort but they eventually reached the room where the whole mess had begun. There was a velvet rope across the doorway, and a little laminated sign that said UNDER CONSTRUCTION - AUTHORIZED PERSONNEL ONLY. Sherlock slipped underneath it without hesitating, and John followed suit.

As before, the room was deadly dark. There was a ladder leaning against the far wall, a box of cardboard stars sitting next to it. The new plasma ball stood in the middle of the room, flickering eerily above its base. 

"All right?" Sherlock called back, and John realized he'd stopped right inside the door. 

"Fine," said John, and went to meet him next to the ball. "Let's hope this works."

Sherlock made a noise of agreement. "Hm. I do so want to start investigating that case."

John chuckled. 

"Count of three, like before. Ready?"

"Yeah."

Oh, he was ready. He was sick and tired of this body, its limbs that were too long, its protruding ribs, its curly, impossible hair. He wanted to be John Watson again with all his scars and faults, his milky fingernails and solid shoulders and eyelashes that nearly vanished in the sunlight. He wanted to know where his limbs would end up when he moved them. He wanted to be short again, for Chrissakes. 

"One."

It hadn't been all bad, really. That shower he'd taken - maybe it hadn't been particularly ethical, but it'd been very, _very_ nice. But - masturbation really wasn't what he'd wanted, was it? It'd be even better to touch Sherlock, _really_ touch him, touch him with his own hands and lips and tongue. He loved that great, brilliant, idiotic soul, and he wanted it back where it belonged.

"Two."

_Please let this work. Please._

"Three." 

Their hands hit the surface of the globe and there it was, that rushing, falling sensation, like he was being pulled down a slide. His eyes jittered shut, and he could see the ball pulse with light behind his eyelids. He felt lighter, suddenly, freer - whatever had been tugging on him was gone. His hand was pushed off the ball by some invisible force and he held it up to his face and looked, and looked, and it was _his_ hand, and _his_ wrist, and he was so overcome with joy that he tackled Sherlock and smashed his lips against the detective's.

Heart pounding, he drew back. "Er," he said. 

Sherlock stared at him, breathing hard. "We did it," he crowed, and now _he_ was the one crushing his mouth against John's, their arms wrapped about each other triumphantly, their legs twining together underneath them.

Sherlock slid a hand behind John's head, his fingers brushing his neck, and the sensation made him sigh happily into Sherlock's mouth. The kiss was frantic and urgent, their tongues winding together wildly, their teeth bumping and clicking, and John adored it. He though his heart would burst through his chest. 

"Hey!" someone said. Their heads snapped around, saw the security guard silhouetted in the doorway. "What are you two doing?"

Sherlock giggled. "Sorry, mate!" he said, and grabbed John's hand. "We'll be off now!"

They dashed past him, avoiding his grasping hands. "This is a _children's museum,"_ he yelled after them.

Cackling wildly, hearts pumping, they sprinted through the building. John settled into the pace easily, savoring the way his body responded, the familiar pace it reached, the feeling of Sherlock's long hand wound through his own. He didn't care how he looked, he didn't care that the jumper Sherlock had chosen to wear for him that morning was one of his very least favorites. He didn't care they were two fully grown men charging through a children's museum hand-in-hand. All he could feel was joy, utter joy at being himself again, at having Sherlock next to him in his own body, at that wonderful, terrifying kiss they'd shared.

They pushed through the security at the entrance and down the front steps, pausing for breath at the bottom. Sherlock waved a hand gleefully into the street. "Taxi!" he shouted.

One pulled over and they got in, hands still clasped together, sitting so close on the lumpy backseat their thighs pressed together.

"221 Baker Street, post-haste," Sherlock said gleefully, and planted another lingering kiss on John's lips.

The cabbie rolled his eyes and, _very_ quickly, dove into the London traffic.


	6. Chapter 6

They reached Baker Street in record time. The farther Sherlock's hand moved up John's thigh, the faster their cabbie seemed to go. He wasn't too keen on having a pair of blokes fuck in his backseat.

They pulled into the curb and they tumbled out of the car, arms entwined about each other. Sherlock started to pull him up the steps. 

"Oi!" the driver yelled. "You owe me!"

John attempted to pull himself from Sherlock's grasping arms so he could reach the driver, but he couldn't - not that he was trying terribly hard - and so he tottered over to the driver's window, Sherlock clinging onto him and nuzzling into his hair the entire way. 

John dug in his pockets and flung a few loose bills through the window. "Keep the change," he said.

The cab pulled away and they stumbled up the steps to their door, Sherlock nipping at his neck as they went. John found he was desperate for contact, that he couldn't find enough, even though he was pressing himself against Sherlock's long woolen coat. He needed closeness - he needed more. 

As soon as the door shut behind him, Sherlock grasped the back of his head and kissed him deeply, pushing him into the wall. John's hands scrabbled at his back, trying to pull him closer, to press their bodies flush against each other. The rest of the world blinked into nonexistence, Sherlock's hot lips and tongue erasing all noise, becoming the center of his universe. He was so wrapped up in the kiss that he didn't notice Mrs. Hudson until she gave a loud, pointed cough.

Sherlock snapped his head around, though he didn't drop his hands from John's face. John peered out from behind his shoulder, his face beet red. He didn't dare look Mrs. Hudson in the eye, so he fixated on a point somewhere above her left shoulder.

"I've got company," she said. "You've got a perfectly good set of private rooms, you know."

Sherlock cleared his throat. He wasn't nearly as red as John, but a tinge of pink still burned at the points of his cheekbones. "Sorry, Mrs. Hudson," he croaked.

She gave them a wink. "Now, don't be sorry - I know how it is. But I'd appreciate if you didn't alarm my guests."

"Yes, Mrs. Hudson."

"Thank you."

She turned and headed back into her flat. 

Sherlock bent and placed his lips against John's neck. His breath ghosted across the sensitive skin, making John shiver with delight. "What say you?" he asked. "Shall we go upstairs?"

" _Please,_ Sherlock."

Sherlock pulled back from him, and the loss of contact left him feeling oddly naked and alone. But then Sherlock grabbed his hand and tugged him up the staircase, and into the flat, and everything was all right again.

Sherlock pushed him back into their closed door, his hands astride John's hips. He lowered his head again and began sucking at John's neck, licking at the skin just underneath his jaw. It was lovely, and pleasant in all the right ways, and he was suddenly all too aware of the erection he was sporting. Part of him wanted to thrust forward to seek precious friction against Sherlock's thigh, and the other part of him wanted to be careful - how comfortable was Sherlock with sex, really? How experienced was he? He didn't want to scare him away, not now - 

"Ah!" John cried. Sherlock had bit down on his neck, teasing it between his sharp little teeth.

Sherlock pulled back at the sound. His eyes were filled with concern. "Are you okay? Did I hurt you?"

"No - oh my God, Sherlock, no. I'm okay. I'm better than okay."

"So that - noise, that was a positive reaction to certain... stimuli?"

John froze, his mind working. He really was inexperienced, wasn't he? He wasn't a bad kisser, though. He wondered where he'd gotten that from.

"Yeah. Yeah, it was positive. Sorta like... here, why don't I - "

He broke off and latched onto Sherlock's neck before he could protest. As they were, he wasn't really able to reach Sherlock's jawline, so instead he pushed aside the coat and the button-down shirt and kissed around his clavicle, slowly working his way up as far as he could reach.

Sherlock's breathing was coming fast and heavy. He took this as a positive sign, and began to suck a bit at Sherlock's long, graceful neck. He let his teeth graze against the skin, and he shuddered beneath his lips, his hands coming up to cling at the small of John's back. 

"Oh," Sherlock breathed. John smiled, his lips turning up against Sherlock's neck. Without warning he opened his mouth and bit - gently, with only the smallest amount of suction he could muster - and Sherlock's knees wobbled.

_"Ahhhh,"_ Sherlock groaned, and then pulled back, surprised at the sound he'd made. 

John grinned wolfishly up at him.

"I see," Sherlock said. "What a strange array of noises human beings emit, don't you think? It's very clever."

"Mmm," said John, leaning back in to plant another kiss on Sherlock's clavicle.

"I think I'd like to catalog these sorts of noises, in particular. Well, yours, mostly. Research conditions aren't ideal at the moment, though, are they?"

"What? Er, no. I guess not," John ventured. His stomach began to sink. Sherlock was treating this as another research project, wasn't he? Another experiment? He was taking notes in his head right now, mapping out his response, and later he'd write up a report, and he'd probably present it as relevant evidence for some pointless case to Lestrade or _Mycroft,_ oh God - 

"I think it'd be much more conducive if we weren't so - er, clothed," Sherlock said, his cheeks reddening. 

A lightbulb in John's brain went off. _Oh dear God,_ he thought. _He's not really conducting an experiment - he's trying to be coy. Oh my God, he's trying to seduce me._

He might as well play along. "I agree, uh - Detective. Let's fix that, shall we?"

Sherlock nodded emphatically, relief flooding through his features. _Christ, he was nervous, wasn't he,_ John realized. _He wasn't sure if it was going to work or not._ The thought was oddly endearing and he smiled happily as he reached for the collar of Sherlock's coat. He tugged it off his shoulders and tossed it onto the sofa - he'd get scolded for that later, wouldn't he, Sherlock was so tetchy about his coats - and pulled at the shirt underneath, trapping Sherlock's mouth in a kiss. 

"Yours too," Sherlock said between kisses, and John hardly had to be asked twice to shrug out of his windbreaker. Sherlock gave up on unbuttoning his shirt and tore it over his head with a frustrated grunt. It landed underneath the sofa. _Well, that shirt's gone forever,_ John thought dreamily, gathering Sherlock's slender form close to his chest and kissing him thoroughly. The detective's fingers picked at John's jumper, managing to pull it up over his bellybutton before John caught his hands.

"Mmph," said Sherlock, disappointed.

John broke away. "I think we ought to relocate the study to somewhere more comfortable before we go any further, don't you think?" He slid his hands down Sherlock's back, absorbing the feel of his soft, warm skin, letting them rest right above the waist of his trousers. With the long woolen coat gone, the bulge in his pants was unmissable, and John couldn't help but feel a bit triumphant. He wanted to see, to touch - but still, he was afraid to scare his flatmate away. This statement, this was his test. If Sherlock was willing to move into the bedroom - well, all bets were off at that point.

Sherlock pushed into him. "Yes, please, yes," he panted, and John didn't need any more than that to make his decision. He grasped Sherlock about the waist and pulled him over to his bedroom door. Sherlock pushed it open with his foot and they stumbled in, their mouths working against each other, their tongues twisting, mapping. 

John pulled back from the kiss, and Sherlock sprawled backwards onto the bed, his lips wet and pink, his hands loose above his head. He was observing John with a heavy-lidded, longing expression that he couldn't ever remember seeing before. He fancied it quite a bit. 

He'd seen this soft, slender body before, with all its hard edges and angles, but it was just so much better when it was Sherlock occupying it. He wanted to please him, to ravish him so thoroughly his brilliant mind couldn't focus on anything but him, to fill him up with lust, and it was all because this was _Sherlock._ It was Sherlock with his aggravating experiments, his collections of body parts in the freezer and toaster and teapot, his easy self-assurance, and John loved it, all of it. 

Sherlock wrapped his knees about John's torso and tugged him down onto the bed. His hands fell at the sides of Sherlock's head, and he used them to lever himself down into another sweet, torturous kiss. Sherlock pressed himself into it, pushing their torsos together, their groins, and John couldn't stop the moan that escaped from his throat when he felt the detective's erection rub against his thigh. Sherlock groaned into his ear, long and low, and the sound reverberated though him. 

He began to rut up against him through their trousers, gently, and Sherlock squirmed and panted beneath him. He reached up and grasped John's arse in both hands, his hips jerking wildly. 

John attacked his neck again, this time employing his lips and teeth in full. He was going to have a bit of bruising in the morning, John realized, and the thought only made him bite harder. 

_"John,"_ Sherlock moaned into his ear. _"Oh,_ John."

He bit Sherlock one more time for good measure and pulled back to see his face, stilling his hips as he went, though he wanted nothing more than to keep going. The detective was panting, brows furrowed, worrying his lower lip with his teeth. He looked utterly lovely and utterly debauched. 

"John," he whispered. 

"Mm?" 

"John, I want you to - to, er - "

He was blushing awfully hard. John looked at him quizzically.

"I want you to fuck me," he managed. "If you don't mind."

John laughed. "Oh my God," he said, and swooped down to kiss him. With one hand, he unzipped Sherlock's trousers, tugging them down his legs, and his cock sprung free, leaking and throbbing against his stomach. John took it into his hand, stroking it gently, and Sherlock's hips jerked up into him.

"Please," he begged. 

"We'll need some sort of... er, lubricant," John said. "For - you know."

"Oh!" Sherlock said. "I've got a bottle of lotion in my top drawer. Will that do? I use it to masturbate - "

John choked, his mind generating images of Sherlock, alone in his room, his slick hand working up and down - 

"That'll be just fine," he muttered. He rummaged around in the drawer, found the bottle by feel, and squirted it liberally into his palm. "Tell me if - if I'm hurting you, okay?"

Sherlock nodded, suddenly shy. "I've never done anything like this before," he said, his eyes momentarily flicking away from John's in - shame? Embarrassment?

"We'll go slow, then," John told him. He kissed his way down Sherlock's torso, down past his belly button, down his inner thigh. "Pull your knees up," he instructed, and Sherlock did so, his knobby ankles settling about John's torso. John reached forward and brushed his fingers just above his entrance, slowly circling and pressing around it. He wormed himself up and pulled Sherlock into a kiss, slipping his index finger inside to the first knuckle as he probed his mouth with his tongue. Sherlock jumped, his eyes going wide.

"You okay?"

"Y - yes," Sherlock said. "Feels weird. Nice."

"I'm going to push in a bit more, okay?" he warned. Sherlock nodded, squeezing his eyes shut. John went slow, sliding his finger up and in as gently as he could. Sherlock wriggled around a bit, pushing his hips down onto John's hand. He started to ride John's finger, slowly at first, and then faster, raising and lowering his body urgently. John watched in fascination.

The angle was a bit different this time, but he was sure, maybe, if he crooked his finger _just so -_

"Ohhhh," Sherlock groaned. "John, more. Please, John - "

John added a second finger and let Sherlock adjust to it on his own terms before he began to press in and out again. Sherlock followed his movements, impaling himself down whenever John pushed upwards. He scissored his fingers apart, opening Sherlock up bit by bit.

He couldn't take any more. "John, please, I need - " 

John obliged, slipping out his fingers and unzipping his trousers. He pressed the head of his cock against Sherlock's entrance and the detective pushed down gradually, slowly letting him inside. John let out a breathy gasp at the sensation, close and warm and sweet and so, so wonderful. He did his best to stay still as Sherlock pulled him in closer, stopping somewhere around the midway point. 

"Sher - "

"John, I want to - can we switch around?"

"Mmph," John said, nodding curtly. They maneuvered about until it was John that was lying flat on his back on the bed with Sherlock knelt over him, his hips hovering above his swollen cock. Again he began the slow slide downward, continuing past the middle and continuing until his bottom was nearly pressed against the front of John's thighs. John hissed with pleasure as he felt Sherlock close up around him. 

"God, Sherlock," he moaned. "That feels - you're _incredible."_

Sherlock laughed and began to move, and John's brain shorted out. Stretched out on top of him, Sherlock was so, so gorgeous, his long, lean stomach rising and falling, his own cock bobbing up and down with each movement he made. He swallowed John up completely, so slick and hot, and John couldn't help but jerk his hips upward to meet him. Sherlock complied, matching his pace, and they reached a feverous pitch, John sliding in, and out, and in again, something warm and hot twining in his gut. 

"Oh, John, John," Sherlock was saying. His eyes were glassy, his hair mussed and tangled, and the fire in his gut sparked and grew at the sight.

"Sherlock, I'm going to - oh, Sherlock, oh my God, fuck - "

He jerked upward, his orgasm shuddering through him, thick and warm and sweet. Sherlock continued to ride him through its entirety, and not too far after he reached his limit as well, his cock spasming its release onto John's stomach. Sherlock flopped off of him, totally sated, and crawled up to wrap his arms about his doctor, resting his curly head on his chest. _This jumper,_ John thought, _was done for._ He found he didn't care one bit. It was ugly, anyway, and for Sherlock he'd ruin a thousand jumpers. A million. 

They lay there like that, John threading his fingers through Sherlock's hair. He was so comfortable and tired and happy, so glad to have his detective's arms about him, his heavy head on his chest. 

Perhaps his trip to the museum hadn't been such a terrible idea after all.


End file.
